Terminal block having an opening therein with normally engaged contacts in alignment with the opening and a plug for engagement with the contacts

ABSTRACT

A terminal block and plug are disclosed, the block comprising a plurality of stacked block members having openings therein, each opening having normally engaged contact means therein, the plug having means for engaging the contacts and being insertable into the openings. The plug is rotatable in the openings to make and break the contact means disposed in the openings.

United States Patent Clifford Frank Boblb Inventor Carlisle, Pa. Appl. No. 358,548 Filed Apr. 9, 1964 Patented Dec. 14, 1971 Assignee AMP Incorporated Harrisburg, Pa.

TERMINAL BLOCK HAVING AN OPENING THEREIN WITH NORMALLY ENGAGED CGNTACTS IN ALIGNMENT WITH THE OPENING AND A PLUG FOR ENGAGEMENT WITH THE CONTACTS 7 Claims, 13 Drawing Figs.

111.8. C1 200/51.07, 20G/51.1, 20G/51.12, 339/186, 339/196, 339/198 Int. C1 H02r 33130 Iieid of Search 20D/51.09,

5l.1,5l.07,51.12;339/186,186M, 183,198,198 G, 198.1, 150 B, 161 B, 196, 176 P; 179/96 [56] v References Cited UNITED STATES PATENTS 1,837,900 12/1931 Ekstrand 20G/51.07 3,222,471 12/1965 Steinkamp.. ZOO/51.07 1,061,852 5/1913 Lawrence... 179/96 1,484,360 2/1924 Polzien 339/176 P UX 1,726,053 8/1929 Brown.... 20G/51.1 2,169,988 8/1939 Norrto 179/96 2,562,592 7/1951 Woodside et al. 339/189 X 3,001,167 9/1961 Chesnutt et 31.... ZOO/51.13 X 3,166,649 1/1965 Frantz et al 20G/51.1

Primary Examiner- David Smith, Jr.

Attorneys-Curtis, Morris & Safford, Marshall M. Holcombe, William Hintze, William J. Keating., Frederick W. Raring, .lohn R. Hopkins and Adrian J. LaRue ABSTRACT: A terminal block and plug are disclosed, the block comprising a plurality of stacked block members having openings therein, each opening having normally engaged contact means therein, the plug having means for engaging the contacts and being insertable into the openings. The plug is rotatable in the openings to make and break the contact means disposed in the openings.

PATENIED ommen www@ SHEET l UF /N V/L'N'lUR. C LlFFomD FRANK Bow@ TERMINAL BLOCK HAVING AN OPENING THEREIN WITH NORMALLY ENGAGED CONTACTS IN ALIGNMENT WITH THE OPENING AND A PLUG FOR ENGAGEMENT WITH THE CONTACTS This invention relates to a terminal block and a plug therefor. More particularly, the present invention is directed to a telephone terminal block and a plug therefor, the combination of which performs a number of operations.

Telephone terminal blocks have been inserted between the plant equipment and subscribers equipment in order to perfonn various functions on telephone circuits, such as, monitoring, test the line circuits, jumper the line circuits, disconnect the line circuits, etc. These terminal blocks and the shoes or plugs therefor have proved to be complicated, some contain moving parts, their versatility is limited and, in general, have not proved satisfactory.

It is, therefore, an object of the present invention to provide a terminal block and plug assembly which is simple of construction and ease of operation and which overcomes the above-mentioned drawbacks.

Another object of the present invention is to provide a terminal block and plug assembly wherein the function being performed and the direction thereof` is visibly indicated.

A further object of the present invention is to provide a ter minal block and plug assembly including a positive locking ar rangement of the plug within the terminal block to prevent accidental removal.

An additional object of the present invention is the provi sion of a terminal block and plug assembly wherein the plug always makes contact with a circuit upon which it is being operated before breaking or shunting the circuit.

A still further object of the present invention is to provide a terminal block and plug assembly wherein the input or output of a plug connection can be readily changed.

A still other object of the present invention is the provision of a terminal block and plug assembly which is reliable, versatile, economical and has a self-cleaning contact feature.

Other objects and attainments of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which there is shown and described an illustrative embodiment of the invention; it is to be understood, however, that this embodiment is not intended to be exhaustive nor limiting of the invention but is given for purposes of illustration and principles thereof and the manner of applying it in practical use so that they may modify it in various forms, each as may be best suited to the conditions of a particular use.

In the drawings:

FIG. l is a perspective part sectional view of the terminal block and plug assembly;

FIG. 2 is a perspective exploded view ofthe plug;

FIG. 3 is a perspective v iew of the plug in assembled conditron;

FIG. 4 is a sectional view taken along lines 4-4 of FIG. 1;

FIG. 5 is a sectional view taken along lines 5-5 of FIG. l; and

FIG. 6A-H are diagrammatic views of different ways by which the present invention may be used.

Turning now to the drawings and more particularly FIGS. l-4, there is illustrated a terminal block TB and plug or shoe members PM. Terminal block TB comprises a plate member I having on each side parallel rows of staggered holes 2 and 3 and each end has a recess 4 (only one being shown) to receive a screw or similar device for mounting purposes. One or any number of such rows of staggered holes may be provided. A number of stacked contact-carrying block members 5 of insulation material, such as, plastic or the like, are disposed on plate member I between the rows of holes 2 and 3. Three such contact-carrying block members are illustrated, but one up to any number can be used.

Each member S has parallel rows of holes 6 and 7 with the holes in one row staggered with respect to the holes in the other row. While only two rows of holes have been illustrated, it is obvious that one up to any number may be provided. The sides and ends of upper surface 8 of member S has an upwardly directed continuation 9 defining a border. Extending upwardly from surface 8 between adjacent holes of the row of holes 6 and the'row of holes 7 are projections 10 having diametrical surfaces 11 which are ar'cuately shaped and coincident with the adjacent holes thereby having the same radii as they have.

Midway between each projection l0 is a slot 12 which divides the projection into equal parts `and this slot continues as a recess 12 downwardly a short distance below surface 8. Projections I0 at one end of the block member as illustrated in FIG. 4 merge with border 9 and have a single surface Il coincident with the end holes. One of these end projections has slot I2 therein while the other projection has extending upwardly therefrom a keying member 13 which mates with a recess 14 in the bottom surface of the adjacent block in engagement therewith to properly align the block members. The other end of the block member is conversely arranged since the outermost hole in one end will be the innermost at the other end due to the staggered relationship. Each end of block member 5 has an arcuate depression 1S in alignment with recess 4 to facilitate engagement with the mounting screw, bolt or nut.

Diametrical slots I6 are disposed in each side of border 9. a pair of which are in alignment with each hole and are contained in the vertical plane in which the axis of the hole is contained. Each pair of slots is also in alignment with a slot l2. Every other slot in each side of border 9 has a recess I7 which is disposed bel'ow surface 8. Each hole has associated therewith a pair of contact elements 18 and 19.

Both contact elements comprise a shank section 20 and a semicircular section 21. Section 20 has spaced inclined recesses 22 into which conductor members (not shown) are to be disposed, a channel 23 formed therein for strengthening purposes and a projection 24.

Section 21 of each contact element extends outwardly from shank section 20 and is more narrow as shown more clearly in FIG. 5. The inner portion of section 2l which includes an angular disposition of about l20l 30 has the same radius while the remainder thereof is substantiallyl straight to the free end which has a rounded edge. The outermost point of the free end is normally in a plane beyond the plane containing the shank section and parallel therewith.

As can be discerned, contact element 18 is the shorter one, and when it is placed inblock member S, shank portion 20 is disposed in slot 16, projection 24 thereof is disposed in recess I7 and semicircular section 21 has a portionlying across the hole with which it is to be associated. Contact element I9 is the longer one, and when it is placed in block member 5, shank portion 20 is disposed in slots 1.6 and I2, projection 24 thereof is disposed in recess l2' and semicircular section 2l has a portion lying across this hole. As shown in FIG. 4, contact elements 18 and 19 form a pair in association with a hole in correspondence therewith, and the rounded free end of one contact element engages the other contact element beyond the point where the semicircular configuration begins. Shank portions 20 are in alignment with a corresponding hole 2, 3 in plate member l through which the conductors pass and then are affixed in recesses 22. One of semicircular sections 2l has an outwardly directed bump 2l' therein.

An upper block member 25 having ends and sides of the same configuration as block members .5 is keyed onto topmost block member S by recesses I4 located in the bottom surface. Holes 26 are located in block member 25 in correspondence with holes in rows 6 and 7, and the part containing holes 26 is about half the thickness of block member 25. Each hole 26 has a diameter less than the diameter of the holes in rows 6 and 7. Semicircular recesses 27 are diametrically disposed in each hole 26 and the distance between both recesses is equal to the diameter of the holes in rows 6 and 7 as illustrated in FIG. 5. Aligned holes (not shown) extend through the block members and plate member 1 to receive screws 28 to secure these members together in stacked alignment, to maintain the contact elements in place and to define staggered aligned openings each of which include at least one pair of engaged contact elements. A channel 29 is disposed in the top surface of block member to receive indicia and projections 30 overlie this channel to hold the indicia therein after it has been threaded into position. l

Turning now to plug member PB and more particularly FIGS. 2 and 3, a stripped multiple-conductor means 3l has a contact member 32 affixed to each conductor 33. Contact member 32 has an almost cylindrical section 34, the free end of which is rounded in the manner as that of contact elements 18 and 19.

A contact-mounting member 35 of insulating material comprises a fiat section 36 having sides 37 which are about twice the thickness of section 36 and are rounded. Diametrical recessed sections 38 are disposed in spaced relationship along each rounded side, which are rounded and of less diameter than the rounded sides but thicker than section 36. The spacing of recessed sections 38 corresponds to the spacing of each pair of contact elementsA 18 and 19 in block members 5. Cylindrical sections 34 of contacts 32 flexibly engage sections 38, and the thickness of sections 34 on sections 38 render the outer surfaces thereof coincident with that of sides 37.

One up to six contacts can be placed on member 35 as illustrated, but, of course, more can be applied by lengthening this member. The flexibility of the material of the contacts maintains them on sections 38.

A portion 39 extends outwardly from section 36 and contains diametrical recesses 40 disposed in the sides thereof. Recesses 40 receive lugs 41 (only one being shown) of a retaining member 42 having a cylindrical part secured to the insulation of conductor means 31. As can be discerned, lug 4l includes an extension 43 whose fiat surfaces engage portion 39 to maintain retaining member 42 in position.

Bottom 44 of section 36 has a configuration similar to that of holes 26 in block member 25; however, the circular part has a smaller diameter than holes 26 but sides 37 will slidably tit into recesses 27 thereof. At the bottom of sides 37 is a discshaped section 45 concentric with the circular part of bottom 44 and which has a diameter slightly less than that of holes 26. Arcuate-shaped openings 46 (only one being shown) are contained in section 45 from one side to the next. A hole 47 extends through the circular part of bottom 44.

A cover member 48 comprises a hollow tubular section 49 having a diameter equal to that of section 45 which fits over contact-mounting member 35 as shown in FIG. 3 and has diametrical slots 50 (only one being shown) to allow sides 37 and cylindrical sections 34 of contact 32 to be exposed. Slots 50 also engage contacts 32 to hold them securely in place. Arcuate-shaped projections 51 are located at the bottom of member 48 which mate with arcuate-shaped openings 46 to hold the bottom of the cover member in place. Holes 52 in member 48 correspond in position to that of hole 47, and a pin 53 passes through these holes to secure members 35 and 48 together to form a plug for insertion into holes 26 and the holes ofrows 6 and 7 in terminal block TB.

Cover member 48 includes a top section 54 which has a hole 55 to allow conductor means 3l to pass therethrough and surfaces 56 projecting diametrically outwardly from section 49 in a direction normal to slots 50 and spaced from the top of these slots a distance slightly in excess of the height of holes 26 in block member 25.

Thus, sides 37 of the plug member and recesses 27 in holes 26 of block member 25 define polarizing means to always insure that the plug member is inserted into one of the aligned openings in the terminal block without engaging and thereby interrupting the engaged contact elements therein. After the plug member has been inserted into one of the aligned openings, whereby surfaces 56 engage the top surface of block memberv 25, the plug member can be rotated 360. At 0 and 180, the plug member can be removed from the terminal block, but any other angular disposition will cause the plug member to be locked in the terminal block because of the normal and spaced dispositions between surfaces 56 and sides 37. This provides a locking means for the plug member to maintain the plug member within the terminal block and to prevent accidental removal therefrom. Part 57 of section 54 is pointed to define an indicating means on the plug member which, in accordance with the functions to be performed, indicates in which direction through the circuit in the terminal block it is being performed. The height between the bottom of the plug member and surfaces 56 thereof corresponds to that between plate member l and the top of block member 25 of the terminal block.

OPERATION The operation of the plug member within the terminal block will be described in connection with FIG. 4. As shown in the bottom pair of engaged contact elements 18 and 19, sections 34 of contacts 32 are within semicircular sections 2l and are in alignment with the shanks of these contact elements; the circuit connected through these contact elements remains connected. Upon rotation of the plug member in either direction, sections 34 engage semicircular sections 2l as illustrated in the middle pair of contact elements and make contact therewith before the contact elements become disengaged; and upon further rotation of the plug member, the contact elements are disengaged from each other. The plug member is rotated as shown by the top pair of contact elements whereupon one of sections 34 engages bump 21 to hold the plug member at this position. Semicircular sections 21 may engage surfaces 1l of projections l0 to limit their movement. Thus, it can be discerned that the present invention discloses a make before break arrangement which can be useful for a number of different functions, some of which will be discussed subsequently. l

lt should be pointed out that by sections 34 engaging semicircular sections 21, there is always provided a wiping action between these engaging sections which is highly desirable because this provides a self-cleaning feature. In addition, when the free ends of semicircular sections are disconnected and reconnected via the action of the plug member, these free ends slidably dsengage and 4reengage the respective semicircular sections so that a self-cleaning action is also performed at these locations on the contact elements.

When the plug member engages the contact elements, contact element 18 will pivot from slot 16 in border 9 while contact element 19 will pivot from slot 12 in projection l0. Since contact element 19 has a longer lever arm than contact element 18, it is the general case that the free end of the semicircular section of contact element 19 will become disconnected from that of contact element 18 before the free end of the semicircular section of contact element 18 becomes disconnected from that of contact element 19. However, regardless of which free end becomes disconnected first or they become disconnected simultaneously, there is a make with the plug member before a break of these contact elements; and, therefore, continuity, if desired, will also be maintained.

As shown in FIGS. l and 5, each aligned opening in the terminal block contains three pairs of contact elements which is the conventional arrangement for telephone circuits; however, the present invention contemplates that the terminal block and plug assembly may conveniently be used in conjunction with other arrangements, such as, for example, the power field with single and three-phase circuitry.

FIG. 6 diagrammatically illustrates a single row of contact elements in plan view and some of the uses of the present invention. FIG. 6A illustrates a broken circuit when it is desired t0 discontinue the circuit such as, for example, to a delinquent subscriber. The plug member, in this instance, has no external connections.

FIG. 6B shows the plug member connected to reproducing means, such as, for example, ear phones to monitor any of the circuits and the contacts on each side are interconnected for this purpose.

FIG. 6C shows two plug members connecting an input circuit to another output circuit since the normal output circuit could be noisy or working improperly for some unknown reason.

FIG. 6D represents crossing the inputs and outputs of two circuits as when subscribers move from different parts of an exchange to other parts thereof.

FIG. @E is similar to FIG 6B in that test equipment is placed in shunt with the circuit to perform a test thereon.

FIG. 6F is directed to a novel manner to test the input and output of a particular circuit. In this example, the plug member has connections to only one side thereof to the test equipment, and the pointed edge of the plug indicates whether the output or input side of the circuit is being tested in order to establish on which side of the circuit the trouble exists.

FIG. 6G and 6H illustrate respectively parallel outputs and parallel inputs between two different circuits.

While the foregoing represent some of the uses of the present invention, others can, no doubt, be visualized to perform other functions.

As can be discerned, there has been disclosed a novel and useful terminal block and plug assembly which is simple to manufacture, easy to operate and provides self-cleaning contacts ofthe terminal block and plug.

It will, therefore, be appreciated that the aforementioned and other desirable objects have been achieved; however, it should be emphasized that the particular embodiment of the invention, which is shown and described herein, is intended as merely illustrative and not as restrictive ofthe invention.

What is claimed is:

l. A terminal block comprising at least one block member having at least one opening therein, contact members disposed in said block member and having semicircular sections in alignment with said opening and with the free ends thereof in normal engagement to define a substantially circular contact area, means in said block member and on said contact members to maintain said contact members in normal engagement and in alignment with said opening, the diameter of said contact area being less than that of said opening, said semicircular sections upon being engaged by contact means of plug means providing contact therewith before the free ends are disengaged, and the free ends in disengaging and reengaging slide along their respective portions of the semicircular sections thereby cleaning these contact areas, and another block member disposed on said one block member and having a hole in alignment with said opening, the diameter of said hole being less than that of said opening, said hole having diametrical recesses with the diameter therebetween being about equal to that of said opening, and recesses mating with corresponding sides of said plug means to polarize insertion of said plug means into said opening without said contact means engaging said contact area.

2. A plug member comprising a dielectric contact-carrying member having rounded sides, contact means oppositely disposed on said rounded sides in recesses thereof to define substantially smooth sides, a dielectric hollow tubular member fitted over substantially the entire length of said contact-carrying member and being provided with slots extending along said sides so that said sides and contact means thereon project outwardly through said slots, and means connecting said con tact-carrying member and said tubular member to lock said contact-carrying member and tubular member together to form a unitary structure, edges of said slots engaging said contact means to thereby hold said contact means in said recesses.

3. A plug member according to claim 2 wherein said contact means are connected to insulated conductor means, strain-relief means having a section secured to the insulation of said conductor means and another section for engagement with said contact-carrying member to provide strain relief for said conductor means. l

di. A plug member according to claim 2 wherein said hollow tubular member includes surfaces extending outwardly therefrom which are disposed in a direction normal to that of said slots and are spaced therefrom.

5. A plug member according to claim i wherein one of said outwardly extending surfaces is pointed to indicate the direction in which said plug member is connected within a terminal block.

6. A plug member comprising a dielectric contact-carrying member having rounded sides provided with spaced and opposed recesses therein, contact members disposed in said recesses and filling same to define substantially smooth sides, a dielectric hollow tubular member extending over the said contact-carrying member and extending along substantially the length thereof, said tubular member having diametrical slots extending along said sides and Contact members so that said sides and contact members thereon project outwardly through said slots beyond said tubular member, and locking means on said contact-carrying member and said tubular member maintaining said contact-carrying member and said tubular member together to form a unitary structure, edges of said slots engaging said contact members and keeping said contact members in place in said recesses.

7. A terminal block comprising at least one block member having at least one opening therein, contact members disposed in said block member and having semicircular sections in alignment with said opening and with the free ends thereof in normal engagement to define a substantially circular contact area, means in said block member and on said contact members to maintain said contact. members in normal engagement and in alignment with said opening, the diameter of said contact area being less than that of said opening, said semicircular sections upon being engaged by contact means of plug means providing contact therewith before the free ends are disengaged, and the free ends in disengaging and reengaging slide along their respective portions of the semicircular sections thereby cleaning these contact areas, and means on said block member coaxial with said opening and matable with the configuration of the plug means to polarize insertion of said plug means into said opening without said contact means engaging said contact area. 

1. A terminal block comprising at least one block member having at least one opening therein, contact members disposed in said block member and having semicircular sections in alignment with said opening and with the free ends thereof in normal engagement to define a substantially circular contact area, means in said block member and on said contact members to maintain said contact members in normal engagement and in alignment with said opening, the diameter of said contact area being less than that of said opening, said semicircular sections upon being engaged by contact means of plug means providing contact therewith before the free ends are disengaged, and the free ends in disengaging and reengaging slide along their respective portions of the semicircular sections thereby cleaning these contact areas, and another block member disposed on said one block member and having a hole in alignment with said opening, the diameter of said hole being less than that of said opening, said hole having diametrical recesses with the diameter therebetween being about equal to that of said opening, and recesses mating with corresponding sides of said plug means to polarize insertion of said plug means into said opening without said contact means engaging said contact area.
 2. A plug member comprising a dielectric contact-carrying member having rounded sides, contact means oppositely disposed on said rounded sides in recesses thereof to define substantially smooth sides, a dielectric hollow tubular member fitted over substantially the entire length of said contact-carrying member and being provided with slots extending along said sides so that said sides and contact means thereon project outwardly through said slots, and means connecting said contact-carrying member and said tubular member to lock said contact-carrying member and tubular member together to form a unitary structure, edges of said slots engaging said contact means to thereby hold said contact means in said recesses.
 3. A plug member according to claim 2 wherein said contact means are connected to insulated conductor means, strain-relief means having a section secured to the insulation of said conductor means and another section for engagement with said contact-carrying member to provide strain relief for said conductor means.
 4. A plug member according to claim 2 wherein said hollow tubular member includes surfaces extending outwardly therefrom which are disposed in a direction normal to that of said slots and are spaced therefrom.
 5. A plug member according to claim 4 wherein one of said outwardly extending surfaces is pointed to indicate the direction in which said plug member is connected within a terminal block.
 6. A plug member comprising a dielectric contact-carrying member having rounded sides provided with spaced and opposed recesses therein, contact members disposed in said recesses and filling same to define substantially smooth sides, a dielectric hollow tubular member extending over the said contact-carrying member and extending along substantially the length thereof, said tubular member having diametrical slots extending along said sides and contact members so that said sides and contact members thereon project outwardly through said slots beyond said tubular member, and locking means on said contact-carrying member and said tubular member maintaining said contact-carrying member and said tubular member together to form a unitary structure, edges of said slots engaging said contact members and keeping said contact members in place in said recesses.
 7. A terminal block comprising at least one block member having at least one opening therein, contact members disposed in said block member and having semicircular sections in alignment with said opening and with the free ends thereof in normal engagement to define a substantially circular contact area, means in said block member and on said contact members to maintain said contact members in normal engagement and in alignment with said opening, the diameter of said contact area being less than that of said opening, said semicircular sections upon being engaged by contact means of plug means providing contact therewith before the free ends are disengaged, and the free ends in disengaging and reengaging slide along their respective portions of the semicircular sections thereby cleaning these contact areas, and means on said block member coaxial with said opening and matable with the Configuration of the plug means to polarize insertion of said plug means into said opening without said contact means engaging said contact area. 